Web cutting mechanism for bag machines



Sept. 15, G \,V POPPE WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept. 10, 1954 7 Shee'ts-Sheet 1 INVENTOR 6f0/P6f M 52 ATTORN EY 10, 1954 7 Sheets-Sheet 2 Sept. 15, 1936. w, POPPE WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept.

Sept. 15, 1936. G. w PQPPE 2,054,297

WEB CUTTING MECHANISM FOR BAG MACHINES ATTOR EY Sept. 15, 1936. G w POPPE 2,054,297

WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept. 10, 1934 '7 Sheets-Sheet 4 ATTORN EY Sept. 15, 1936. 6, w. POPPE WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept. 10, 1934 7 Sheets-Sheet 5 INVENTO'R Qmvf /1/ Pap/ ATTORNEY Sept. 15, 1936. w po p 2,054,297

WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept. 10, 1954 7 Sheets-Sheet 6 //6 I 24 fi L W 7'' //0 /6 //g 0 ATTORNEY Sept. 15, 1936. G w pOppE 2,054,297

WEB CUTTING MECHANISM FOR BAG MACHINES Filed Sept. 10, 1954 7 Sheets-Sheet 7 I N V E N TOR 620/965 M POPPE ATTORNEY Patented Sept. 15, 1936 PATENT oFFIcE WEB CUTTING MECHANISM FOR BAG MACHINES George W. Poppe, Brooklyn, N. a Y., assignor to Equitable Paper Bag 00. Inc., Brooklyn, N. Y.,- a corporation of New York Application September 10, 1934, Serial No. 743,338

12 Claims.

The present invention relates to a machine for making paper bags and more particularly to improvements in the means for making cuts in a web of paper prior to folding the same to form a bag tube which is finally to result in a bag such as shown and described in my Patent 1,798,168, granted March 31, 1931.

In said patent, the flap of the bag is produced by first making cuts in a web of paper, the cuts being spaced from the edge of the web and running generally in-alongitudinal direction. These .cuts are made prior to folding the web about the former of a bag machine to form a bag tube. In said patent two forms of cutting devices are shown. In Figure 5 I show slitter knives which make cuts in the web parallel to the edge thereof, while in Figures 6 to 8 inclusive are shown dies which are set at a slight angle to the line of feed of the web. In both cases, however, the slitter knives and the dies are mounted to rotate as shown in Figure 2 of said patent.

Bag machines such as shown in said patent may be adjusted to make bag tubes of different lengths and this is accomplished by varying the speed at which the web is fed in relation to the intervals between the cutting off of the tube to form a bag tube length. The shaft carrying the dies in said patent rotates once for each bag and in order to make a good cut the peripheral speed of the die should be substantially the same as that of the web. Hence it is the practice to provide a number of dies, each of a different radius.

It is also desirable to make the flap of the bag of different lengths for different type bags. This means that the cuts I30 shown in Figure 11 of said patent must be of a length necessary to produce the proper length flap and therefore a different pair of dies must be provided for each different flap length.

The dies must be accurately shaped and accurately ground and this not only entails the provision of a large stock of dies but the maintenance of the dies in proper condition involves considerable time and expense.

One of the objects of the present invention therefore is the production of a machine for making a bag such as described in said patent in which a wide range of bag tube lengths and flap lengths may be obtained. In one form only a single pair of dies or cutting tools are necessary. In another form which the invention may take, "a series of pairs of such tools are used.

To the accomplishment of this object, instead of having the dies mounted for rotary movement as in said patent, I provide means for giving to the dies a rectilinear movement and the dies may therefore have straight edges.

A further feature of the invention resides in the provision of means for moving a pair of dies or cutting tools in a rectilinear path and varying the time interval during which the dies and web are in operative relation.

- A further feature of the invention relates to the 1 provision of means whereby a pair of dies are moved in a rectilinear path at the same surface speed as the web during the time that the dies and web are maintained in operative relation.

In one form of the invention the surface speed of the die is in exact correspondence to the surface speed of the web.

In a modified form which the invention takes the surface speed of the die or cutting tool is substantially that of the surface speed of the web, although not exactly so.

Further features and advantages will become apparent from the following detailed description and claims when taken in connection with the accompanying drawings in which- Figure 1 is a top plan view of a bag machine showing my improvements applied thereto;

Figure 2 is a side elevation of a portion of the right-hand end of the machine of Figure 1;

Figure 3 is a section on the line 33, Figure 1, looking in the direction of the arrows;

Figure 4 is a section on the line 4-4, Figure 1;

Figure 4a is a bag tube section before the bottom is folded to make the complete bag;

Figure 5 is a side elevation of the machine from the opposite side of that depicted in Figure 2 Figure 6 is a fragmentary section on the line 6-45, Figure 1, of the cam mechanism for controlling the cooperative relation between the paper web and the cutting tool;

Figure 7 is a top plan view of a portion of the mechanism shown in Figure 6 looking in the direction of the arrow;

Figure 8 is a section on the line 88, Figure 1;

Figure 9 is a perspective view showing the cam and connections from said cam for moving the dies;

Figure 9a is a perspective view of the die carriage and associated parts;

Figure 10 is an enlarged detail view of the cams shown in Figure 6;

Figure 11 is a part top plan view and part sectional view of the structure shown in Figure 10,

' the section being along the line "-4 I, Figure 5;

Figure 12 is a detail of one of the elements making up the cam structure;

Figure 13 is a section on the line 13-" of Figure 14 showing a modified form of the means for moving the cutting tools or dies in a rectilinear path;

Figure 14 is a top plan view of the mechanism v shown in Figure 13;

Referring to Figure 4 of the drawings, the machine to which my improvements are applied is designed for making either type of bag shown and described in my aforesaid Patent 1,798,168 and its general construction and mode of operation is similar except insofar as such construction and operation is modified by the improved mechanismwhich will be later described.

As in said patent, there is the usual supporting framework 2 which carries the various mechanisms constituting the operative parts of the machine. A web of paper 4 from which the bags are fashioned is fed from a roll 5 mounted on a shaft 8 supported by the side frame members 2. The web passes over guide rollers 1 and I and over a reversing roller l0 and another guide roller I2 on its way to the former l4 about which the web is folded in the usual manner to form a bag tube. The former is supported by a central column l5 depending from a bar It extending across the machine and secured in the side frames thereof.

As the web passes over the roller Ill it is supplied with a line of paste by means of a paste disc l8 rotating in a paste pot 20, Figures 1 and 4, as is usual in machines of this character. Small rollers 2| mounted on flexible arms 22 act on the web just after it is folded to properly guide it as it passes to the feed rollers 24, these rollers constituting the feeding mechanism for the web as well as for the tube. After the tube passes the feed rollers it is severed into bag lengths by mechanism which is shown and described in said patent. This mechanism includes the so-called pinch bars 26 which rotate once for each bag to be formed and which momentarily grip the tube and retard its motionsufilclently to create a slack in the tube in order that it may be properly severed. The lower wall of the tube is severed by the serrated edge 28 of the former l4 while the upper wall of the tube is severed by the lip knife 30 suitably supported in brackets 32 as shown more clearly in Figure 1.

The severing of the tube is accomplished as usual by the so-called striker bar 34 carried by sprocket chains 36, one on each side of the machine as shown in Figure 1. The manner in which these various parts are driven will be described more in detail hereinafter, as well as the timing of the various parts.

The mechanism so far described is similar to that shown in my said patent and the mechanism now to be described relates to the improved means whereby cuts are made in the web preliminarily to folding the same about the former to produce the bag tube.

In the form of invention shown in Figures 1, 4, and 8, the cuts in the web which are to form the sides of the closing flap of the finished bag are made by a pair of dies 40 mounted for recipsides are fianged as shown in Figures 8, 9, and 9a and each shoe is guided between the to'p edge of an inwardly projecting portion 46 of the side frame members and the under side of a bar 48 the bars 48 being suitably supported at their ends by the frame members of the machine as shown in Figure 1. A shaft 50 passes through the left hand end of the shoes as indicated in Figures 4. 9, and 9a. At each end this shaft, Figures 4 and 9, has secured to it a pinion. 52 and each pinion engages a rack 53 secured to the inwardly pro- Jecting portions 46 of the frame members as indicated in Figures 8 and 9a. Twocollars 54 are pinned to the shaft 50 near the center thereof and between these collars is pivoted a link 56 having a pin and slot connection with a second link 51. Link 51 is also slotted at $8, the slot engaging the shaft I9 which supports the cam 42. As shown in Figure 1, the side frame of the machine is suitably shaped to provide an arm 60 which serves as a bearing for one end of the shaft 59, the other end passing through the side frame 2 by which it is supported.

The parts above described comprising the shaft 50, shoes 45, and U-shaped bar 44 constitute a carriage for supporting the dies, which carriage is moved positively in one direction by the cam 42 at each rotation thereof. A cam follower 62 is pivoted to the forward end of the link 51 and rides on the operative face of the cam whereby its movement is imparted to the die carriage. Return movement of the carriage is effected .by means of springs 83, one on each side of the machine. One end of these springs is attached to pins 64 projecting from the shoes 45 while the other ends engage pins 65 secured to the frame of the machine.

The working face of the cam 42 is so shaped that the movement imparted to the die carriage by the cam is uniform.

To cause the dies to make the proper length of cut in the web I have provided means whereby the web and dies are brought into cooperative relation at definite intervals and maintained in cooperative relation for an interval of time sufficient to cause the dies to make a cut of the proper length. Of course different length cuts could be made by providing dies of different lengths but since one of the objects of the present invention is to reduce the number of different types of dies which must be provided and maintained in condition, I prefer to use dies of a length sufllcient to make the longest cut desired.

The mechanism for accomplishing this purpose is of the following construction:

Situated about midway between the rollers I 0 and I2, Figure 4, is an anvil roller 66 mounted for eccentric movement on the shaft 61. The shaft 61 is supported in the side frames of the machine and the anvil roller 58 extends across the machine beneath the path of movement of the dies. Preferably the roller 66 is of hardened steel and the dies are resiliently mounted in their respective holders. The specific mounting of the dies is not shown in the present application but may be similar to the construction shown in Figures 6 and 7 of my Patent 1,798,168 previously referred to. The shaft 61 is rocked. by a pair of series of cams which may be adjustable to determine the interval of time during which the paper web and dies are maintained in operative relation. For this purpose, the left hand end of the shaft 81 is provided with a crank arm 98 to which is pivoted one end of a link' 69 (see Figures 1, 4, 6 and '7). The lower end of the link 99 is slotted as shown in Figure 6 for the purpose of guiding the link in its movement, the said slot engaging the shaft I0 upon which cams I2 and I9 are adjustably mounted. The link is provided with a cam follower I4a by which the link is positively moved in one direction under the action of said cams. The link is moved in the opposite direction by a spring 14b connected between a pin on the link 99 and some portion of the frame work of the machine as illustrated in Figure 4.

The details. of the cams and their method of adjustment will be described hereinafter but assuming that by different adjustments of the cam the anvil roller 56 is maintained in its raised position for different intervals of time, then it will be readily seen that the length of the cuts made in the web by the dies 40 will depend solely upon the length of this time interval provided, of course, the dies are moved at the same linear speed at wh'. ch the paper web is traveling during the time that operative relation between the dies and the paper web is maintained.

Before describing the way in which diflerent length bags are produced and different length cuts, it will be in order to describe the timing of certain parts and the manner in which they are driven.

The various parts of the machine are driven from a motor I4, Figure 1, which through belt and pulley connection drive shaft I5 upon which shaft the lower pinch bar 29 is mounted. Within the upper or left side frame member 2, Figure 1, said shaft I5 carries a gear I9, Figure 5, which meshes with a gear II on the upper pinch bar shaft I8, the two shafts being driven therefore in a 1-to-1 ratio. The shaft I5 is connected to drive the shaft I0 carrying cams I2 and I9 by means of a sprocket chain I9 which passes about a sprocket on the shaft I5 and about a similar sprocket 15a on the shaft I0, Figure 11. A tension roller BI supported by a stud shaft 02 projecting from. the side frame member 2, Figure 1, keeps the sprocket chain I9 at the proper tension.

The shaft 59 carrying cam 42 is driven from the shaft I0 through a sprocket chain 89 passing over a sprocket 84 on the shaft I0 and a similar sprocket 85 secured to a sleeve I05 on the shaft 59. A tension roller 86, Figures 4 and 5, keeps the sprocket chain 93 at the proper tension. The

sprocket wheels are all of the same pitch diameter so that the shafts I5, I0 and sleeve 95 are all driven in the same ratio. The actual drive of the shaft 59 from the sleeve I05 is through a clutch mechanism which will be presently described.

This machinei's adapted to make bags of any length within the capacity of the machine. It may be adjusted also to make a flap of any length within the capacity of the machine.

For every rotation of the pinch bars 26 a bag tube length is severed from the main tube by the striker bar 34 and the gear ratio between the pinch bars and the feed rollers 24 is such that the gear 92 which engages a broad-faced gear 94 on the lower feed roller shaft. This change gear mechanism is usual in machines of this character and its purpose is to produce bag tubes of different lengths. As a practical example, if the gear contains forty-one teeth, then the feed rollers 24 will be of such diameter that they will advance the tube 12.87 inches at each rotation in the making of a 12 inch bag with a one inch flap. The bag tube, of course, must be longer than the finished bag because of the flap and the folding-in of the bottom of the bag. The actual bag tube length is the distance between the lines a-a and b-b, Figure 4a. when the bottom is folded along 0-0 and the upper flap folded down the actual bag length is-the distance between the lines 0-0 and d--d.

If the earns 42 were of such contour as to move the dies 40 at the same speed as the paper with the gear 90 driving the. feed rollers, then if it were desired to make a longer bag, a larger gear such as 09 having. say 42 teeth, would be brought into mesh with the gear 92 so that the feed rollers would be driven at a greater speed with each rotation of the pinch bar shaft. In such a case it would be necessary to change cam 42 and substitute a cam of larger size and different contour in order'that the linear speed of the die be the same as the linear speed of the web. Thus a variation in the length of bag is compensated for by different cams but the length of the slit depends upon the interval of time during which the web and dies are maintained in operative relation and hence on the adjustment of the cams I2 and I3. This adjustment is effected in the following manner:

Referring to Figure 11,' which is an enlarged view of the cams looking at them in the direction of the arrow, Figure 6, there is provided a hub 95 which may be clamped to the shaft I0 by means of a screw 91. The hub 99 isformed with an enlarged cylindrical portion 98 and a flanged portion 99. The cams I3 and I2 in the order named are slipped over the cylindrical portion 99 of the hub and to provide for a third cam, if required, a split washer I00 is slipped on beside the cam I2 and screws IOI threaded into the cylindrical portion 98 hold all of thesemembers for movement together with the hub and provide means whereby the two cams I2 and I9 may be adjusted with respect to one another to vary the thrust of the link 69. A third cam I02 shaped such as shown in Figure 12 may be slipped on in place of the split ring I00 when it is desired to use a third cam. I

Since the shortest bag which it is contemplated making on this machine is about I2 inches long and the shortest lip with which such a bag is ordinarily provided is one inch, each of the cams I2 and I9 have an operative cam surface extending-over 30 of arc. Therefore, when the two cams are closed, their action on the follower 140. will be such as to hold the anvil roller 90 in raised position for about one-twelfth the period of rotation of the shaft I0. At the same time, assuming that the change gear 90 is in use then the feed rollers will, during one rotation, feed 2 hence the actual length of the flap will approximate one inch. In practice, the length of the cuts as determined by the cams I2 and 13 will be determined by experiment. It is of course possible to provide graduations on the cams and to set them approximately by such graduations, but

skilled adjusters are able to make the proper adjustment by trial with greater facility than if scales were provided. While only one extra cam I02 has been shown it is of course obvious that another extra cam could be provided if necessary,

to make a longer slit than could be made .by having the two cams l2 and I3 separated to their full working extent as indicated in Figure 10. Likewise cams of longer working may be substituted for the 30 cams 12 and II. For instance, with three cams of 30 working surface a flap length of about three inches could be made on a 12 inch bag. If the working surface of each cam were then only two cams would be'necessary for such a length flap.

The purpose of the collar 96 with its clamping screw 91 not only serves to hold the cams on the shaft but also affords a means of adjusting the cams about the shaft 10 in order that the time at which the cams begin to act may be properly coordinated with the action of the pinch bars since the cuts for the bag must be made at bag length intervals apart and must be at such position in respect of the time of cutting off of the bag tube that the edges 20 and 30 of the former and lip knife respectively may sever the tube along lines which meet the ends of the cuts.

A similar adjustment is provided for the cam 42. and hence thesprocket 85 as previously described is secured to a sleeve I05,Figure 1, which sleeve at its other end is provided with a disc I00 having a series of holes within its periphery (see Figure 3). A disc I01 similar to the disc I06 is provided wtih a slot I08 and a screw I09 passes through the slot in the disc I01 and may engage in any one of the holes in the disc I06. The disc I 01 is provided with a short hub by which it is p nod to the shaft 59. By this means the cam 42 m y be correctly timed with the pinch bars and with the cams I2 and I3.

In Figure 4 the cam is shown in normal position and in making one rotation from said position the carriage carrying the dies is moved to the left, Figure 4, and at the proper time during thismovement the cams I2 and 13 act to raise the anvil roller 06 and maintain it raised for the length of time necessary to make the proper length of cuts in the web. As soon as the cams I2 and I3 cease to act the anvil roller 06 is immediately returned by the spring 14b. If a very short out has been made the cam 42 may still continue to move the dies leftwardly as viewed in Figure 4, but at this time they are not in cooperative relation with the web and hence there is no further cutting action. Just as soon as the follower 62 drops off the high part of the cam the die carriage is returned to normal position by the springs 63, Figure 1.

It is important that during the time that the dies are in cutting contact with the web that they are properly supported against any movement upwardly and to this end there is provided a pair main frame members 2 of the machine.

single pair of dies is necessary to make any length of out within the capacity of the machine. The diesmove in a straight path and their edges are straight, although the dies may be set at 'an angle to their longitudinal movement in order to make the diagonal cuts such as shown in Figure 1. It will also be noted that the proper speed to be given to the dies is obtained by substituting diiferent cams 42 instead of by substituting different dies as has heretofore been necessary.

Also in the form of mechanism heretofore described the linear speed of the dies is always equal to the linear speed of the web during the time that the web and dies are in cooperative relationprovided always, of course, that the proper cam 42 is used corresponding tothe ratio of drive between the pinch" bars and feed rollers.

In Figures 13 to 18 inclusive I have shown a modified form of cutting means in which the dies are mounted on sprocket-chains and in which the linear speed of the dies in relation to the speed of the web may be maintained approximately. but not exactly for all bag lengths within the capacity of the machine. At this point it may be stated that the present machine is intended to make bags from about 12 inches in length up to about 16 inches in length. Referring to Figure 13, the web 4 is fed over rollers I0 and I2 corresponding to the rollers I0 and I2 of the previously described construction, and the anvil roller 68 is operated by cam mechanism which may be an exact duplicate of the cam mechanism already described. The two constructions differ mainly in the manner of mounting and controlling the dies. In the modified construction the dies I I4 are arranged in' three pairs -and are carried by rods 8', which rods may also serve as pivots for links of the two sprocket chains 8 which pass over sprocket wheels I20 and I22 supported in a frame indicated generally by the reference character I24 and which may form part of or be separately attached to the The sprocket chains after leaving the sprocket wheels I20 are maintained in a horizontal position by guiding sprockets I20 mounted on a shaft I21, Figures 13 and 14. Since it is. not feasible to use sprocket links smaller than one inch it will be assumed in describing the operation of this modified form of mechanism that the links of the chains I I8 are one inch links and that the sprockets I20 and I22 have a corresponding pitch.

In order that the lineal speed of the dies during their cutting operation may approximate the lineal speed of the paper web it is contemplated that sprocket wheels I22 having different numbers of teeth be used according to the tube length for which the change gears 88, 00 and 00 are set. The smallest wheel I22 which would be used in the present machine is shown in Figure 13, while the largest would be of such diameter that the sprocket chains would pass to said wheels in a substantially straight line from the guiding sprockets I20.

For different bag lengths it is also necessary to lengthen the chain and in order to compensate for this the shaft I28 upon which the sprocket wheels I20 are journalled is mounted in blocks through which pass the adjusting screws I30.

The pressure plates I I0, Figure 13, are constructed in the same manner as has been already described in connection with the construction 7 shown in Figure 4 for example.

' sist of parallel tracks I3I and I32 between which the chain travels. I3I maybe a projecting portion of the frame of the machine and I32 may be an angle bar suitably secured to the inside of the frame as shown in'Figure 16.

The drive from the motor is substantially the same in this modified construction as in the construction previously described, the motor driving the lower pinch bar shaft I5 from which motion is transmitted by the sprocket chain I9 to thesprocket 15a. on the shaft 10. In the present construction, however, the shaft I0 carries a gear I33 meshing with a similar gear I33 on a shaft I34,

which latter shaft carries a sprocket for drivingthe sprocket chain 830. similar in construction and mode of operation to the sprocket chain 03 previously described. Therefore, the sprocket wheel I22 is driven in a one-to-one ratio with the pinch bar shafts.

The number of teeth on the sprocket I22 and the length of the chain I I8 are such that for each rotation of the sprocket I22 the chain H8 is driven one-third of its entire travel so that one die is brought into position to act on the web. Three-sets of dies, however, are provided for mechanical convenience. The'principle of operation, of course. would be the same if a shorter chain were used and but one set of dies employed. The longer chain, however, gives room to more conveniently get to the parts for the purposes of adjustment and there is also less wear on the dies.

.When a gear I22 is changed for a gear of a greater number of teeth an extra link must be inserted in the chain IIBbetween each pair of dies.

With this construction and mode of operation the lineal speed of the pair of dies is not precisely the same as the linear speed of the web but the difierence is so small that it is not a serious disadvantage. I

It'has been previously stated that the change gear for making a 12 inch bag with a one inch flap would have M teeth and that the diameter of each feed roller would be such as to feed the web 12.87 inches for each bag. Under these conditions the sprocket I22 would be provided with thirteen teeth and there would be thirteen links in the chain between the pair of dies. At each rotation of the sprocket I22, therefore, the dies would be moved thirteen inches while the paper web would be moved only 12.87 inches during the same time. This difference in speed ratio, however, is so small as to be practically negligible insofar as the smoothnessof'the out which the dies will make in the paper web is concerned. It may be stated that the change gears 88, 89, and 90 difi'er from each other by one tooth, which one tooth difference makes a difference of approximately of an inch in bag tube length or more correctly, .312 of an inch difference. In choosing the correct size sprocket I22, therefore, that size which would give the smallest diiference in relative speed between web A still further modification of the means ror moving the dies is shown in Figures 17,18, and 19. This form resembles the form' first describedin that the dies are mounted in a die carriage constructed and operating in exactly the same manmar as in the first described construction. The

difference, however, is in the substitution of a different type of carriage moving means for the cam 42-used in the first form. For the cam 42 is substituted a disc I30, Figure 19 which is pinned to the shaft 50 and partakes of its movement of rotation. The disc is provided with a central groove, the sides of the groove beingparallel to a diameter and in said groove is a slide I38 having a projecting cylindrical portion I39 to which the link 51 is pivotally attached by means of a screw I40. An adjusting screw I42 permits adjustment of the slide within the slot to vary the throw of the link 51.

The position of the parts as shown in Figure 17 may be considered the zero or dead center position of the disc I30 with the dies 40in their extreme right hand position. when the machine is operated the disc I30 rotates in the direction of the arrow, Figure 17, and during the first stages of its movement moves the dies at relatively low speed, which speed reaches a maximum when the center of the screw I40 is 90 from the position shown in Figure 17. The speed then decreases and again becomes zero at from the position shown in Figure 17..

In order that the speed of the die and the speed of the paper may approximate each other, the timing of the parts is such that the dies and web are not brought into cooperative relation until the center of the pin I40 has moved approxi- -mately 45 from its zero position and the dies and cooperative relation is established during the time that the center I40 is moving through 45 of arc. A scale may be provided on the disc I36 as shown at I44, Figure 16, and a pointer may be provided on the slide to adjust the slide for different tube lengths. If the adjustment is such that the speed of the dies and the speed of the web are equal at a position 90 from that shown in Figure 17, then by adjusting the slide so that the screw I40 is further from the center of the disc I36 the dies and web will be moving at equal speeds at some point either side of 90 position. Hence, even though the speed of the dies and web are not always equal, the differential is never large enough to be of practical disadvantage. This construction, moreover, permits the use of but a single set of dies for all bag lengths within the capacity of the machine and but one disc I36 is necessary.

The length of cuts which the dies make is determined by adjustment of the cams 12 and I3 which act to move the link 69, Figure 17, and hence to determine the time interval during which the dies and paper web are in cooperative relation exactly as in the first described form of means for feeding a web of paper, a former about which the web is folded to produce a bag tube, of means for making pairs of longitudinal cuts in the web prior to folding the same about the former, said means including a pair of cutters and means for. moving said cutters in a straight line in'contact with the web and for maintaining said cutters and web in contact for a period sufllcient to make cuts of the desired length.

2. In a bag machine the combination with means for feeding a web of paper, a former about which the web is folded to produce a bag tube, of means for making pairs of longitudinal cuts in the web prior to folding the same about the former, said means including a pair of cutters and means for moving said cutters in a straight line in contact with the web at substantially the surface speed at which the web is being fed and for maintaining said cutters in contact with the web for a period suflicient to make cuts of the desired length.

3. In a bag machine the combination with feed 1 rollers for feeding a web of paper, a former about which the web of paper is wrapped to form a tube and pinch bars for holding the web during severancepf the tube, of a pair of cutters, means for moving said cutters and web into contact at intervals and in timed relation with the pinch bars, means for moving said cutters rectilinearly at substantially the speed at which the web is fed by said feed rollers and means for varying the time during which the cutters and web are in contact while maintaining the relative linear speed of the cutters and web unchanged.

4. In a paper bag machine, the combination with means for feeding a web of paper, and a former about which the web is folded to produce a bag tube, of means for making a cut in the web, means for moving said cutting means in a straight line, means for establishing cooperative relation between the web and said cutting means at definite intervals during the feeding movement of the web, and means whereby the time during which the cooperative relation between the web and the cutting means is maintained may be varied.

means for feeding a web of paper and a former about which the web is folded to produce a bag tube, of means for making pairs of longitudinal cuts in the web spaced from the edges thereof prior to folding the web about the former, means for moving said cutting means in a straight line in cooperative relation with the web and means for varying the time during which such cooperative relation is maintained.

6. In a bag machine the combination with means for feeding a web of paper and a former about which the web is folded to produce a bag tube, of a pair of dies for making longitudinal cuts in the web prior to folding the same about the former, a cam and means controlled thereby for moving said dies in a straight line in operative relation with the web, said cam being so shaped as to move said dies in a straight line at uniform speed during the time the web and dies are in cooperative relation.

7. In a bag machine, the combination with a support over which a web of paper passes, a former about which the web is wrapped to form a bag tube and feeding means for the web, of means for making a pair of longitudinal cuts in the web prior to folding the same about the suflicient to cause said dies to make cuts of a pre-- determined length.

8. In a bag machine, the combination with a support over which a web of paper passes, a former about which the web is wrapped to form a bag tube and feeding means for the web, of means for making a pair of longitudinal cuts in the web prior to folding the same about the former, said means including a pair of dies and means to move said support to bring said web and a pair of dies into cooperative relation at intervals during the feeding movement of said web and means for varying the interval oftime during which the web and dies are maintained in cooperative relation.

9. In a bag machine the combination with a support over which a .web of paper passes, a former about which the web is wrapped to form a bag tube and feeding means for the web, of a pair of cutters for making paired longitudinal cuts in the web prior to folding the same about the former, said cutters adapted to make said cuts in said web while the web is passing over said support and for maintaining said cutters and web in contact for a period sufllcient to make cuts of the desired length, and means for giving to said cutters a rectilinear movement during the cutting operation.

10. In a bag machine the combination with means for feeding a web of paper and a former about which the web is folded to produce a bag tube, of a series of pairs of cutters for making longitudinal cuts in the web prior to folding the same about the former, a sprocket chain supporting said series of pairs of cutters, and means for so supporting and guiding said sprocket chain that a pair of cutters carried thereby move in a straight line parallel with the feeding movement of the web during a portion of their travel.

11. In a bag machine the combination with means for'feedinga web of paper and a former about which the web is folded to produce a bag tube, of a series of pairs of cutters for making longitudinal cuts in the web prior to folding the same about the former, a sprocket chain supporting said series of pairs of cutters, means for so supporting and guiding said sprocket chain that a pair of cutters carried thereby move in a straight line parallel with the feeding movement of the web during a portion of their travel, and means for bringing the web and cutters into contact at definite intervals.

12. In a bag machine the combination with means for feeding a web of paper and a former about which the web is folded to produce a bag tube, of a series of pairs of cutters for making longitudinal cuts in the web prior to folding the same about the former, a sprocket chain supporting said series of pairs of cutters, means for so supporting and guiding said sprocket chain that a pair of cutters carried thereby move in a straight line parallel with the feeding movement of the web during a portion of their travel, and means for bringing the web and cutters into contact during a definite interval of time, and means for varying said time interval.

GEORGE W. POPPE. 

